This invention relates to a process for producing corrosion resistant silicon nitride bodies. More particularly, it provides a silicon nitride composition from which corrosion resistant silicon nitride bodies can be produced.
In general, silicon nitride by itself has limited usage. In order to produce materials for turbines, cutting tools, wear parts and the like, composites are needed which can be pressed to give bodies with special properties such as corrosion resistance. Presently yttrium oxide and aluminum oxide are used with silicon nitride to produce bodies which are resistant to corrosion.
This invention involves the use of lanthanum oxide with or without aluminum oxide with silicon nitride as a composition which when hot pressed produces a body having better corrosion resistance than that which is produced by the yttrium oxide-aluminum oxide-silicon nitride material.